Don't let Da Rock scare you, Get a 4-stroke.

The ASP 61 will have as much or more power than your 46LA (The LA series is not known for their overwhelming strength) and it will burn less fuel.

The ASP 61 is 6 oz heavier than the 46LA. This usually means shifting your battery back, or NOT adding the nose weight many planes need if you're using a 2-stroke. At the absolute MOST, you'll have to add 2oz of tail weight to compensate (Probably more like 1 1/2) for the 6oz difference.

If you're flying 3-D, weight is a major concern. If you're not - it's not - period. Contrary to popular belief, lighter planes do NOT fly better - heavier planes (Within reason of course) slice through the air and are less effected by winds.

Now I will admit that there are some planes that I prefer to use a 2-stroke on, but they are few and far between. And when I do use a 2-stroke, I'm usually left cursing out the slimy, oily mess they spit all over the airplane. With a 4-stroke, there are many days when, after flying, I put my airplane back in the car without having to clean it.

Beginners are often swayed away from 4-strokes mainly due to the expense. They are no more difficult to operate than a 2-stroke. True, they do like a little more nitro content than a 2-stroke, but they burn much less fuel, so the extra cost is a non-issue.

Ok, so the weight, and the cost of fuel is not an issue, but the initial price is. Is it worth it to have a more efficient engine, that gives you better, smoother throttle response?

Oh yea, and don't forget that cool 4-stroke sound! How many full-scale Extra 300s have that anemic 2-stroke sound?

How many Harleys or Triumphs use a 2-stroke?

You wanna fly an airplane, or fly a dirt bike?